diff --git a/htdocs/install/mysql/migration/17.0.0-18.0.0.sql b/htdocs/install/mysql/migration/17.0.0-18.0.0.sql
index 09feb039ac3..2910ccee23b 100644
--- a/htdocs/install/mysql/migration/17.0.0-18.0.0.sql
+++ b/htdocs/install/mysql/migration/17.0.0-18.0.0.sql
@@ -41,3 +41,4 @@ ALTER TABLE llx_facture DROP COLUMN amount;
 -- Rename prospect level on contact
 ALTER TABLE llx_socpeople CHANGE fk_prospectcontactlevel fk_prospectlevel varchar(12);
 
+ALTER TABLE llx_facture ADD COLUMN prorata_discount	real DEFAULT NULL;
diff --git a/htdocs/install/mysql/tables/llx_facture.sql b/htdocs/install/mysql/tables/llx_facture.sql
index 7377d7803a7..6e54df4eb32 100644
--- a/htdocs/install/mysql/tables/llx_facture.sql
+++ b/htdocs/install/mysql/tables/llx_facture.sql
@@ -39,7 +39,7 @@ create table llx_facture
   date_pointoftax		date DEFAULT NULL,									-- date point of tax (for GB)
   date_valid			date,									-- date validation
   tms					timestamp DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,								-- last modification date
-  date_closing				datetime,						-- date de cloture
+  date_closing				datetime,							-- date de cloture
   paye					smallint DEFAULT 0 NOT NULL,
 
   remise_percent		real     DEFAULT 0,						-- remise relative
@@ -62,7 +62,7 @@ create table llx_facture
   fk_user_author		integer,								-- user making creation
   fk_user_modif         integer,                                -- user making last change
   fk_user_valid			integer,								-- user validating
-  fk_user_closing			integer,						-- user closing
+  fk_user_closing			integer,							-- user closing
   
   module_source			varchar(32),							-- name of module when invoice generated by a dedicated module (POS, ...)
   pos_source			varchar(32),							-- numero of POS terminal when order is generated by a POS module, IDsession@IDwebsite when order is generated for a website basket.
@@ -81,18 +81,20 @@ create table llx_facture
   note_private			text,
   note_public			text,
   model_pdf				varchar(255),
-  last_main_doc			varchar(255),					-- relative filepath+filename of last main generated document
+  last_main_doc			varchar(255),							-- relative filepath+filename of last main generated document
 
   fk_incoterms          integer,								-- for incoterms
   location_incoterms    varchar(255),							-- for incoterms
 
   fk_transport_mode     integer,								-- for intracomm report
 
+  prorata_discount		real DEFAULT NULL,  					-- % of the prorata discount (to know how to add prorata discount lines for each vat rate in the invoice)
+
   situation_cycle_ref smallint,  -- situation cycle reference. A key that is similar for all the serie.
   situation_counter   smallint,  -- situation counter. The number into the serie: 1, 2, ...
   situation_final     smallint,  -- 0 by default, 1 it if is the final invoice.
 
-  retained_warranty							real DEFAULT NULL,  -- % of retained warranty
+  retained_warranty							real DEFAULT NULL,  -- % of the retained warranty (to calculate the amount to pay later)
   retained_warranty_date_limit				date DEFAULT NULL,
   retained_warranty_fk_cond_reglement		integer  DEFAULT NULL,			-- payment condition of retained warranty
 
@@ -100,9 +102,9 @@ create table llx_facture
   extraparams			varchar(255),							-- for other parameters with json format
   
   fk_multicurrency		integer,
-  multicurrency_code			varchar(3),
+  multicurrency_code		varchar(3),
   multicurrency_tx			double(24,8) DEFAULT 1,
-  multicurrency_total_ht		double(24,8) DEFAULT 0,
+  multicurrency_total_ht	double(24,8) DEFAULT 0,
   multicurrency_total_tva	double(24,8) DEFAULT 0,
   multicurrency_total_ttc	double(24,8) DEFAULT 0
 )ENGINE=innodb;